What 393.87 means in plain language
FMCSR 393.87 requires that any cargo or equipment extending beyond the rear or sides of your vehicle must be flagged with appropriate warning markers. These flags alert other drivers to the hazard posed by your load's overhang, reducing the risk of collisions and crashes caused by reduced visibility or unexpected obstruction.
The rule is straightforward: if your load projects past the vehicle's boundary lines, it must be marked. The marking itself is typically a red flag, reflector, or similar device positioned to make the overhang plainly visible to following or adjacent traffic, especially in low-light conditions. A missing, damaged, or inadequately positioned flag—or a projecting load with no flag at all—constitutes a violation.
This is a vehicle maintenance and equipment compliance issue, not a cargo-securement violation. The inspection officer is checking whether your truck's warning systems are in place and functional, not the tightness of straps or the stability of the load itself.
What our enforcement data actually shows
Our inspection records show that 393.87 has generated zero citations across our entire database of 13 million+ roadside inspections. Over the last 12 months, we recorded zero citations, and in the last 90 days, zero citations as well. Across all historical inspection records, no vehicle was placed out of service for this violation, and no vehicle avoided out-of-service placement—the OOS rate is 0.0%.
This is a striking finding. Despite being a codified safety requirement, this specific violation appears either to be extremely rare in the real-world fleet population, or to be cited only under circumstances so exceptional that our database has not yet captured an instance. For a driver who has just received a 393.87 citation, this puts the violation in a unique enforcement category: uncommon enough that few peers will have faced it, yet serious enough to appear in the FMCSR and warrant inspection attention.
The CSA severity weight assigned to 393.87 is 3, a moderate penalty score in the Federal Motor Carrier Safety Administration's enforcement algorithm. However, because the violation is not OOS-eligible, even if cited, it will not result in immediate removal from service.
Who gets cited most
Because our database contains zero citations for 393.87 across all states and all carriers, we cannot identify top jurisdictions or carriers by citation count. There is no geographic or operational pattern to report at this time.
If you have received a 393.87 citation, you may be among the first drivers in our dataset to be cited for this specific violation—or your case may represent a rare enforcement action in your state or region.
How severe is this compared to similar codes
Within the vehicle maintenance category, 393.87 sits apart from its peer violations in one critical way: it has zero enforcement history in our data, while similar codes show substantial citation activity.
For example, 393.9(a) — Inoperable required lamps — has generated 660,737 citations and carries a 15.4% out-of-service rate. This lamp-related violation is far more frequently cited and is substantially more likely to result in OOS placement. Similarly, 396.3(a)(1) — Inspection/repair/maintenance general — has 236,919 citations and a 45.3% OOS rate, making it one of the highest-consequence vehicle maintenance violations in the dataset.
Other peer codes like 393.11 (Lighting devices/reflectors) with 179,734 citations and a 1.8% OOS rate and 393.78 (Windshield condition defective) with 157,894 citations and a 0.3% OOS rate show active enforcement but remain far more common than 393.87.
The data indicates that warning flags on projecting loads, while technically required, are not a frequent focus of roadside inspection enforcement. This does not mean the requirement is unimportant—only that your citation may reflect either a clear and observable violation or a heightened inspection focus in your region.
How to avoid it
If you regularly haul loads that extend beyond your vehicle's footprint, implement these driver-level practices before every trip:
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Inspect all flag mounting hardware before departure. Check that flag posts, brackets, and fasteners are secure and not bent or broken. A loose or missing mounting point can allow a flag to fall away mid-trip, leaving your load unwarned.
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Verify flag condition and visibility. Ensure all flags are intact, not torn or faded, and clearly red or red-and-white as required. Flags weathered by sun or damaged by prior loads may not provide adequate warning to other drivers.
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Confirm flag placement against your actual load. Before accepting a load that projects, walk the length and width of your vehicle with the cargo in place. Mark the exact points where the load overhangs, then confirm a flag is installed and positioned to cover that overhang from the rear and from both sides.
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Double-check clearance in low-light conditions. If you're pre-tripping at dawn or dusk, mentally note whether an inspector at night could clearly see your flags. Position them high enough and with enough reflective surface to catch a following vehicle's headlights.
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Review your trailer's documentation. If your trailer is equipped with permanent or semi-permanent flag mounts (common on flatbeds or drop-deck trailers), confirm the fleet's maintenance program includes regular inspection and replacement of flags. A flag that was installed correctly three months ago may have been dislodged by wind or impact without your knowledge.
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Know your carrier's load acceptance process. Some fleets prohibit loads that project, eliminating the risk entirely. Others allow projection only with dedicated flagging procedures. Make sure you understand your company's policy and that you can execute it reliably before every dispatch.